Hi everyone! So i want to build Eddy Bergmanns ARP2600 Envelope follower on stripboard but I want to add an adjustable high pass filter to the input.
Here is the stripboard:
Where would you add that high pass filter? I was thinking adding it after the Preamp input / Bypassed input switch. A 100nF cap and a 100k pot with 100R resistor in series, would that work? How would you incorporate that?
cheers
you speak about RC filter, Sam put it on the output of this for example
but like he said on the schem it’s more Tone that a filter
but it’s a low pass not hi, and i think that a real filter would be better
like this simple one (with hi pass)
thanks. i just need a simple high pass, without resonance. just one knob to control the frequency.
i want it in the envelope follower, because i like putting drum machines into envelope followers and then taking the generated envelope into the pitch of an oscillator.
so basically the drum machine generates a melody.
if you add a high pass filter before the envelope out, you can control the melody in a strange way.
i do it with my ms20 mini a lot:
at 0:34 i turn up the high pass filter of the ms20s envelope follower the first time.
the patch was opz into the external signal processor and then the generated envelope cv routed to oscillator 2.
cool sound ! so a RC filter should do the job
i find this to test the value
https://www.amplifiedparts.com/tech-articles/filter-low-pass-high-pass
work in progress
It works! Herr is a small jam:
What confuses me a little is that the line in audio is not routed to the audio output. And i think i might have wired the hpf pot backwards, but who cares 
Fantastic work Klaus!
Thanks man! I just replied to your post on ig
Sorry but i don’t want to make some mistake, can you please make me a little drawing for the HPF pot with cap and R, and where is exactely the connection on the board
thx a lot
hi, unfortunately i don’t have access to my modular for the next few weeks. but with hindsight you don’t really need that hpf, as i realized the filter does not affect the audio signal, but just the signal into the envelope follower.
so it only kind of interacts with the threshhold knob (envelope follower input level knob in eddys layout) but the audio won’t be filtered which is what i hoped for.
ok thank you ! …
Dang, thanks for bumping this thread, hadn’t seen it before. Very cool technique! Love the true Kosmo panel.
Just an idea, if you add another RC HPF on the audio out, after with a double potentiometer, you can with one pot control 2 filters, on for each out (Env and Audio)
A question, this module have a Mic input, an Instru input and a Line input, but no Synth input. so we can’t use it with another module with synth signal ? or it only make to create an envelope with an external source ?
it’s not really clear for me … thx
At the worst, a passive attenuator (@Dud I know you have a module with some) in series with the line-in and voila.
i’d just try the instrument and line inputs for synth signals. but what is the point here? the module generates envelopes out of what you run into it. so if you for example run a droning oscillator into it, the generated envelope will just have infinite sustain. if you run single notes, cut off by a vca or filter into it, the envelope will look the same as the one used to control said vca or filter.
i mostly use it to generate envelopes from drummachines.
i think the who used it with guitar to vca, so the synth voice would duck whenever there is something played on the guitar.
